Authentication

Nansen account API calls accept a selected nansen:api browser session or conventional API key with the same permissions. NANSEN_API_KEY takes precedence; optional primaryEnv preserves configured-key injection. Run nansen auth status for offline selection. Cached access expiry alone permits automatic renewal during an authorized task. Stop on anonymous selection, invalid state, blocked/uncertain renewal or actual auth failure; never drop a credential or fall back to anonymous x402 payment. Browser login does not grant wallet signing, privileged service identity or a persistent MCP integration key. Preserve all confirmation, signing, sanctions and geographic checks below. Browser login is available in CLI 2.0.0 within the macOS arm64 preview scope.

Wallet

Auth Setup

Use a selected nansen:api browser session or conventional API key for Nansen account API calls. Agents should inject NANSEN_API_KEY through their environment or secret manager and use commands directly; no login is needed to persist it. Human terminal users can use explicit nansen login --human for legacy key setup. With an already injected environment key, that explicit mode saves it without prompting and requires the native auth lock binding.

# Free live check of the effective API credential
nansen account

Plain nansen login instead requests fresh browser approval. It does not save an environment key or grant wallet signing/RPC authority. Wallet custody and provider credentials below remain separate.

Wallet Providers

The CLI supports two wallet providers:

Privy Wallet Creation

Privy wallets are server-side wallets managed by the Privy API. No password is needed — keys never touch the local machine.

Prerequisites

The following environment variables must be set:

Create a Privy wallet

nansen wallet create --provider privy
# Or with a custom name:
nansen wallet create --name agent-wallet --provider privy

Critical rules for agents (Privy)

• No password needed — Privy manages keys server-side
• Cannot export keys — wallet export only works for local wallets
• All other operations (list, show, send, delete, default) work identically for both providers

Local Wallet Creation (Two-Step Agent Flow)

This section covers local wallet creation. For Privy server-side wallets, see the Privy Wallet Creation section above — no password is needed.

Wallet creation requires a password from the human user. The agent must NOT generate or store the password itself.

Step 1 (Agent → Human): Ask the user to provide a wallet password (minimum 12 characters).

Step 2 (Agent executes): Run the create command with the password the user gave you.

NANSEN_WALLET_PASSWORD="<password_from_user>" nansen wallet create

After creation, the CLI automatically saves the password:

• OS keychain (macOS Keychain, Linux secret-tool, Windows Credential Manager) — secure, preferred
• ~/.nansen/wallets/.credentials file — insecure fallback when no keychain is available (e.g. containers, CI)

All future wallet operations retrieve the password automatically — no env var or human input needed.

If the .credentials file fallback is used, the CLI prints a warning on every operation. To migrate to secure storage later, run nansen wallet secure.

Password resolution order (automatic)

1. NANSEN_WALLET_PASSWORD env var (if set)
2. OS keychain (saved automatically on wallet create)
3. ~/.nansen/wallets/.credentials file (insecure fallback, with warning)
4. Structured JSON error with instructions (if none available)

Critical rules for agents

• NEVER generate a password yourself — always ask the human user
• NEVER store the password in files, memory, logs, or conversation history
• NEVER use --human flag — that enables interactive prompts which agents cannot handle
• After wallet creation, you do NOT need the password for future operations — the keychain handles it
• If you get a PASSWORD_REQUIRED error, ask the user to provide their password again

Create

Privy (server-side, no password)

nansen wallet create --provider privy
# Or with a custom name:
nansen wallet create --name trading --provider privy

Requires PRIVY_APP_ID + PRIVY_APP_SECRET env vars. No password needed.

Local (encrypted on disk, password required)

# Ask the user for a password first, then:
NANSEN_WALLET_PASSWORD="<password_from_user>" nansen wallet create
# Or with a custom name:
NANSEN_WALLET_PASSWORD="<password_from_user>" nansen wallet create --name trading

List & Show

nansen wallet list
nansen wallet show <name>
nansen wallet default <name>

Send

# Send native token (SOL, ETH) — password auto-resolved from keychain
nansen wallet send --to <addr> --amount 1.5 --chain solana

# Send entire balance
nansen wallet send --to <addr> --chain evm --max

# Dry run (preview, no broadcast)
nansen wallet send --to <addr> --amount 1.0 --chain evm --dry-run

Export & Delete

# Default is REDACTED — shows addresses only, never private keys
nansen wallet export <name>

# Write private keys to a file only the owner can read (0600, refuses to overwrite)
nansen wallet export <name> --file <path>

# Print private keys in plaintext to stdout (explicit acknowledgement required;
# warns on stderr when stdout is an interactive terminal)
nansen wallet export <name> --reveal

# Password auto-resolved from keychain (needed for --reveal / --file)
nansen wallet delete <name>

Prefer --file over --reveal: plaintext on stdout ends up in terminal scrollback, shell logs, and agent transcripts.

Forget Password

# Remove saved password from all stores (keychain + .credentials file)
nansen wallet forget-password

Migrate to Secure Storage

nansen wallet secure

For detailed migration steps (from ~/.nansen/.env, .credentials, or env-var-only setups), see the nansen-wallet-migration skill.

Flags

Environment Variables